Remote Access/Control Linux Lite 3.x

[donbrew]

Why copy the service unit?  What is the use of having 2 of them.  Why do either, it is already installed in /lib/systemd/system?
Why bother editing graphical.target
you don't need to enable x11vnc.service?  But do need to enable graphical.target?
Why reboot?

Or, is it all different in 5.6?

All I did was:
sudo apt install x11vnc
sudo systemctl start x11vnc (maybe not needed)
sudo systemctl enable x11vnc
Then I did the password thing.